Air cleaner



March 11, 1941. EN I 2,2341% AIR CLEANER Filed May 25, 1938 Ihllllllllllllllllllz11111,,

33 I! IIIIIIIIIIIIIIIIIIIII" ll [30 1m 32 Pa 1.

INVENTOR FL .2.

j CARL BLARSEN BY a I I I l I A TTORNEYS.

Patented-marrllgm ll y NlT ED STATES 2,234,136 AIR CLEANER.

Carl B. Larsen,

Company,

Racine, Wis., assignor to J. I. Case Racine, Wis., a corporationApplication May 25, 1938, Serial No. 209,890

7 Claims.

The present invention relates to air cleaners for internal combustionengines and the like and an object of the invention is to generallyimprove the construction and operation of devices of this class. i

A further object is to provide such a device which will be highlyemcient under low load'or idling conditions as well as under medium andheavy load conditions,

Further objects are to provide, in a liquid 'washed type of air cleaner,improved means for distributing the liquid, particularly under low .loadconditions; improved preliminary cleaning d liquid atomlzing means;improved labyrinth w means for receiving the liquid; improved means formixing the liquid with the incoming air and for limiting the amount oiliquid carried into the labyrinth: storage means for liquid in thevicinity of the labyrinth; means for returning stored liquid to thelabyrinth; means for preventing bypassing of dirt-laden air past thelabyrinth; means for trapping particles of liquid about to be carriedout of the cleaner and various expedients for the realization of theabove objects.

w Other objects and advantages will appear from the followingspecification and accompanying drawing in which: 1

Figure 1 is a substantially axial sectional view of a cleanerillustrative of the invention.

Fig. 2 is a reduced vertical sectional view taken on the line 2-2 ofFig. l.

Like reference characters have been applied to the same parts throughoutthe drawing and specilication.

As seenin Fig. l the device comprises a labyrinth or cleaner chamber C,a liquid sump or tank T, on air inlet passageway I, and a suctionpassageway S, all related as hereinafter described in detail.

Cleaner chamber C and tank T are for convenience in the present instancemade as castings fitted together at the joint i, a gasket l beinginterposed if desired, whereby the device may be very readily opened forcleaning, but other arrangements for facilitating this are contemplatedas equivalent, Intake passageway I extends downwardly to a point wellbelow the liquid level as represented by the line L, terminating in alip 2 beneath which all the air entering the device must pass throughthe liquid chamber, the depth of liquid when at rest at the lip beingquite-substantial, although it is to be understood that the invention isnot to be taken as limited to this depth or in fact in any manner exceptas defined 55 in the claims.

A dam 3 in the present instance extends across the sump having its topapproximately at the level of the liquid when at rest, and so disposedas to define a chamber l of relatively limited volume about the lip 2and a second chamber 5. During heavy load conditions or when there is alarge flow of air in inlet I a large part or nearly all of the liquid inthe chamber 4 will be swept out of the chamber. by the air stream andcarried upwardly into the cleaner chamber. By virtue of the dam 3 theremainder of the volume of the tank, namely chamber 5, is not afiectedby the air stream, and the volume of liquid so carried up by the stairis thus limited to the contents of chamber A passageway 6 is provided,in the present instance through the dam although it might be otherwiselocated within the contemplation of the "invention, the capacity thereofbeing so chosen as to allow sufllcient liquid to flow from chamber 5 topromptly replenish chamber 4 upon sudden reduction in the flow of air inpassageway I, such as would result upon a sudden change from heavy tolight load conditions. Thus the lip 2 is main-,

tained deeply immersed in liquid substantially at all times during lightload operation, assuring the best possible atomization of the liquid andthe carrying up of a relatively large quantity into the cleaning chamberformed in any desired manner, but in the present instance it is made bya tool introduced through an opening subsequently closed by a plug tPassageway 6 also feeds a metered quantity of liquid intochamber 4during-heavy load conditions to insure the presence of sumcicnt liquidin the vicinity of lip 2 for eiiicient atomization, but insuiiicient toexceed the capacity of the cleaning chamber to separate the liquid fromthe air and return it to the tank.

To further facilitate such atomization a screen or reticulated elementgenerally designated as '1 and in the present instance for conveniencecomposed of a box-like member having sides 8, 9, ill, I I, is fittedinto the space between lip [and dam 3 and held in place by anyconvenient means such for example as a spring hook or thelike I2, whichmay conveniently engage passageway 6, although other expedients forfastening the hook or screen are contemplated as within the scope of theinventlon,

Upper and lower sides '8 and I0 are active in screening the in-comingmaterial, side In being submerged in liquid, and side 8 being locatedapproximately at the suriace of the liquid when quiet. These screensassist materially in the C. The passageway may be breaking up of theliquid and mixing it with air, and they serve to intercept coarsematerial such, for example, as chafl', before it can be carried up intothe cleaning chamber C.

Another important function of the screen box I is to break up thebubbles of air passing through the liquid at light loads to preventtheir being large enough to carry any substantial amount of "dry" dustin their centers, as will happen if the bubbles are large.

Cleaning chamber C contains a mat or pad of fibrous or like materialgenerally designated as l3, for example crimped, tangled or matted wireproviding a labyrinth of fine passageways therebetween into which themixture of air, liquid and dirt is carried from chamber 4, the liquidparticles being intercepted along with the dirt by means of thelabyrinth material, the air passing upwardly and the liquid and dirtworking back down against the air flow and dropping into the sump ortank.

The mat or labyrinth i3 is, for convenience, divided into portions l3and i3 (although it might constitute a single body of material withoutdeparting from the invention) the/former being supported on a screen orreticulated elementl4 forming the lower element of a box-like chamber orcasing i5 carried in a diaphragm i6 interposed between cleaner chamber Cand tank T so as to completely prevent the passage of air into thecleaner chamber except through the cas- -ing I5.

fill the box substantially to a screen H which.

projects over the edge thereof and into contact with the walls ofchamber C as shown, the remainder of the chamber being filled by meansof pad l3 to the level of a screen or reticulated element l8 engaginglugs or the like i9i9 for holding the cleaner element againstdisplacement by the suction of the engine.

Pad I 3 may be firm enough to be self-supporting and screen I1 may beomitted, within the contemplation of the invention.

The projecting of the labyrinth material i3 past the upper edge of boxi5 provides a space or reservoir 20 between the walls of the casing andthe cleaner chamber and above diaphragm l6 into which part of the liquidreturning down-, wardly from the labyrinth material will drain. Thisfurnishes a body of liquid, in contact with screen I! under manyconditions of operation, some of which liquid may be drawn up into anygaps or cracks/that may exist between the labyrinth material i3 and thewalls of chamber C to seal them with liquid, and positively prevent thepassage of any dirt-laden air past the pad and directly to the engine.Furthermore, reservoir 20 is sealed against upwardflow of air except ata hereinafter described passageway ill by diaphragm i6 and the walls ofbox i5, passageway 21 being sealed by the hydrostatic head of liquidthereabove against the relatively low pressure difl'erential existing atthis point, and, accordingly, under ordinary conditions no air hasaccess to reservoir 20, so that all the, air passing through pad l3 mustnecessarily enter the pad through the box or casing i5, and at pointssubstantially spaced from the edges or points of contact of'the pad withthe walls of casing C. Therefore no air can reach the said walls withoutfirst passing through at least a portion of pad i3". It is thereforevirtually impossible for any air to get through the cleaner withoutfirst passing through at least part of one of the cleaning pads or laby--rinths-a common source of trouble in known forms of air cleaners beingthe passing of uncleaned air between the pads and walls,

' Passageway 2| leads from reservoir 20 into the body of labyrinthmaterial in box I5, in the present instance above screen I, and acts tosupply a relatively large quantity of liquid to the labyrinth materialfor a considerable length of time after the flow of air through thedevice is reduced upon a change from heavy to light load conditions, theflow through this passageway 2| being largely or entirely preventedduring heavy loads by the strong upward draft of air and the resultingreduction of pressure in the neighborhood of screen I! below that atpassageway 2|. Thus in the event that this reduced flow of air isinsufiicient'to carry any substantial quantity of liquid upwardly fromchamber 4 more liquid will be supplied from reservoir 20 to preventdrying out of the labyrinth material. Under certain conditions of loadit is possible for liquid to flow constantly from passageway 2 I,reservoir 20 being constantly replenished by liquid carried up by theair stream. It is also possible for chamber 4 to be replenished byliquid flowing over the top of the dam under certain conditions.

Under usual conditions of operation the period of light load or idlingwill be terminated before the liquid in reservoir 20 is exhausted, butin the event "that the idling period is continued beyond this timesufiicient liquid will have reached chamber 5 and found its way intochamber 4 to fill the latter substantially to the line L so that lip 2will be submerged in liquid to its maximum depth, whereupon the'passageof a relatively small volume of air will sufllce to carry a sufficientlylarge volume of liquid into the labyrinth material to insure thoroughsaturation thereof.

Under these conditions the thorough mixing and breaking up of the aircaused by the screen I is particularly beneficial.

Above screen i8 is arranged a baflie' 22, a second baille 23 extendingtoward baflle 22 so as to direct the outgoing air from a pointsubstantially over the center of pad t3 the air in the present instancepassing somewhat to the right as seen in Fig. 1 and then turning to'theleft as indicated by the arrows in order to pass down the suctionpassageway S. Any particles of liquid which may have escaped thelabyrinth material will have a tendency to continue through the spacebetween the bafiles in a substantially straight line to be precipitatedapproximately at 24 against the upper surface of the suction passagewayS, the liquid then running back down the walls of the passageway. Any ofthe liquid which accumulates above baiile 23 may drain back into thelabyrinth through a port 25.

The various parts may be held together in any suitable manner but in thepresent instance cleaner chamber C is permanently attached and supportedon the engine (not shown) and passageway S is connected with thecanburetor inlet 26 by means of an elbow 2'! permanently connectedbetween chamber C and the inlet. Tank T is removably maintained in airtight manner against diaphragm I 6 as for example ,by a tension rod 28fixed with chamber C as by a screw 29 and supporting, through a nut orthe like it, a strap 3| engaged beneath the tank and pressedupwardlythereagalnst by means of I a hand nut 32 or similar expedient, threadedon Bill did

dill

a stud 33 in the present instance fixed with elbow ill, the strap havinga slotted engagement with stud ill.

e tank may thus be readily removed by l.

loosening nut 32 and swinging strap 3| to one side. The used liquid andaccumulated dirt may be removed and the tank recharged with fresh liquidand replacedby reversing the above process. With the tank removed screeni may be talten out and cleaned by disengaging spring ll. irompassageway i. I

The operation of this embodiment should be apparent from the abovedescription, it being noted that lip 2 may be deeply submerged in liquidso as to obtain highly eilicient cleaning oi the air under low loadconditions without the disadvantage of carrying over of liquid into theengine under heavy loads such as has been the eirperience in priorstructures, although it is to be understood that numerous ieatures oithe invention are useful apart from their association with the deeplysubmerged lip.

This freedom from carrying over oi liquid is brought about by therelatively limited capacity oi the chamber i and also by the last thatthe reservoir it accumulates and holds a substantial portion oi theliquid which is swept out at the charrrber t under heavy load operation.e labyrinth is accordingly not overloaded under these conditions and theliquid charge stays in the cleaner.

tin the other hand upon sudden change lrom heavy to light load operationthe depleted liquid in chamber t is almost instantlyrepiaced by liquidirom chamber 5 through passageway and by the substantial amount oiliquid that is led intothe labyrinth through the passageway ill iromreservoir 20, the cleaning being iar superior under low and varyingloads to that which has been done in known forms of cleaners.

"The inverted gable or wedge shape of the screen it aids inconcentrating the returning liquid in the neighborhood of the ridge N toassist in its return to the sump T.

The above being a complete description oi an illustrative embodiment ofthe invention, what is claimed as new and desired to be secured byLetters Patent of the United States is:

l. in an air cleaner a labyrinth chamber, a liquid sump below saidlabyrinth labyrinth in said chamber, a suction passageway leading fromthe chamber, an air inlet for the chamber opening into the sump beneaththe liquid level therein, means for regulating the amount of liquid thatwill be carried up by the air flow into the labyrinth, a reservoirassociated with the labyrinth removed from communication with said sumpand disposed to receive liquid draining from said labyrinth and arrangedfor holding a quantity of liquid during heavy'load conditions and meansior conducting the stored liquid thereinto during light load conditionsto supplement the supply oi liquid in-said labyrinth carried thereintoby the reduced flow of air from said air inlet.

2. In an air cleaner a cleaner chamber, a liquid sump, an air inlet forthe cleaner, terminating in a position to cause liquid to be entrainedin the air entering therein and carried up into the cleaner chamber, alabyrinth pad in the cleaner chamber, a

leading to the labyrinth chamber and arranged with the edges thereof incontact with the walls of the chamber, and a reservoir above said sumpand removed from communication therewith said reservoir being arrangedto '-receive liquid solely from said pad and to maintain a body'oiliquid, when said reservoir is substantially full, at the point ofcontact of the pad with the chamber whereby to provide, under conditionswhich will maintain said reservoir substantially full, a liquid seal forany space that may occur between said walls and pad.

3. In an air cleaners diaphragm dividing the cleaner into upper andlower portions, a liquid sump in the lower portion, and the upperportime including a cleaner chamber, said diaphragm providing anopening,'- walls donning a casing supported from the diaphragm andcountcating with the opening, said walls being spaced ircm the walls atthe cleaner chamber to term a reservoir between said chamber and easing,a labyrinth pad in the casing, is second labyrinth pad above the casingand donning the upper lit oi the reservoir, a passageway leading he thereservoir into the casing, and means ior conducting air into thecleaner, entraining a liquid from the camp, and conducting cleaned airout at the cleaner chamber.

i.. in an air cleaner, a liquid sump, an air inlet terminatingbelow theliquid level in the sunm, a dam in the sump arranged to divide the sameinto a chamber associated with the air inlet and a separate chamberremoved thereirom, a meter ing opening in the dam and a reticulatedclement ertended between the inlet and dam through which air must passon its way irom the inlet,

in place in said cinema is. In an air cleaner a cleaner chamber, aliquid sump, an air inlet for the cleaner, terminating in a position tocause liquid to be entrained in the air entering therein and carried upinto the cleaner chamber, a labyrinth pad in the cleaner chamber, andmeans arranged to ect air with entrained liquid from the p into the padat points spa irorn the edges thereof whereby to prevent air i'rom beingbypassed around the pad without being cleaned, and means including areservoir adapted to be maintained substantially lull of liquid underheavy load conditions and positioned for maintaining a body or liquid incontact with the pad and in position to seal any space inadvertentlyexisting between the pad and the cleaner chamber.

6. In an air cleaner a cleaner chamber, a liquid sump, an air inlet torthe cleaner. terminating in a position to cause liquid to be entrainedin the air entering therein and carried up into the cleaner chamber, alabyrinth pad in the cleaner chamber and arranged with the edges thereoiin contact with the walls of the chamber, means arranged to direct airwith entrained liquid from the'sump into the pad at points spaced fromthe points oi contact oi. the edges thereof with the walls or thechamber, and means including a reservoir adapted to be maintainedsubstantially full oi liquid under heavy load conditions and positionedfor maintaining a body of liquid in contact with the pad and in positionto seal the joint between the pad and chamber, whereby to preventdirt-laden air from passing through any spaces that may inadvertently beleft between the pad and said walls without passing through the pad.

7. In an air cleaner a body portion constituting a chamber, a wallwithin the chamber spaced y from the body to form an air intakepassageway.

a liquid sump engageable with the chamber and having a wall portionconstituting an extension of the above-mentioned wall, said wallsdefining an air inlet peway extending beneath the level of liquid insaid sump, adam in the sump positioned to divide the same into first andsecond liquid chambers, saiddam extending approximately to the surfaceof the liquid within the/ sump, a reticulated element within the flrstchamber and extending between the said extension wall portion and saiddam, spring means for removably retaining said reticulated element inplace within said chamber, a diaphragm interposed between said chamberand said liquid sump ass-5,730

and having an opening therein, a casing extending through said openingand upwardly into said chamber to form 'a liquid'reservoir betweenitself and said chamber, a labyrinth pad in said casing. a passagewayleading from said reservoir into said pad. a second pad in said chamberresting on the upper end of said casing and overhanging said reservoir,opposed inclined baiiies positioned above said second pad and arrangedto influence the flow of'air from approximately the middle of the upperpad, a precipitating surface positioned to receive air directed by saidbaflies and a suction passageway leading from the vicinity of saidprecipitating surface at a sharp angle to the direction of movement ofair past said bailies.

CARL B. LARSEN.

